I’m buying a new product that qualifies for the tax credit. How do I know which components associated with it are also eligible for the credit? For example, for a qualified roof, would the nuts & bolts, be included?

IRS has not issued specific written guidance on this question.

The rule of thumb that has become informal IRS guidance is that if the component is a critical piece of the product's energy efficiency then it is covered, but if it’s the same component that you would use on a non-qualified product (a regular roof), then it would not be covered.

The following products are probably not covered by the tax credit:

• nuts & bolts, and gutter for a new roof 
• hearth, stovepipe or chimney for a biomass stove
• new ducts for an air conditioner or furnace 

You can also contact the IRS directly: www.irs.gov/contact